The Supreme Court has declined five times to intervene in partisan gerrymandering cases, but opponents hope the sixth time will be a charm. In two landmark cases Tuesday, the high court is considering whether congressional districts set by North Carolina Republicans and Maryland Democrats gave their candidates an overwhelming advantage during the past decade. A decision against either state could signal a change in the way legislatures controlled by one party determine their election districts. Chief Justice John Roberts, who has sided with liberal justices in several key cases, looms as the deciding vote.

Barring a last-minute court challenge, a federal ban on bump stocks – devices that can make semi-automatic rifles fire almost as rapidly as a machine gun – will go into effect Tuesday. Bump stocks came under scrutiny after the 2017 Las Vegas massacre, in which a gunman killed 58 people and injured 800 others while using one. In December, the Justice Department ruled that existing bans against fully-automatic weapons also covered bump stocks. Owners have until Tuesday to destroy the devices or turn them in at an office of the Bureau of Alcohol, Tobacco, Firearms and Explosives. Failing to do so carries a $250,000 fine and a possible 10-year prison term.